Gas burner unit

ABSTRACT

A gas burner unit for providing a discharge of a combustible gas to mix with the surrounding air so as to support a flame. The gas burner unit has gas-receiving and gas-discharging chambers which are defined, in part, between a pair of opposed longitudinally extending sidewalls which define between themselves a narrow longitudinally extending slit through which the gas-receiving and gas-discharging chambers communicate with each other. At the gasdischarging chamber these walls are of an undulatory, wavy configuration and are &#39;&#39;&#39;&#39;in phase&#39;&#39;&#39;&#39; so that the alternating ridges and depressions of one wall are respectively in alignment with the alternating depressions and ridges of the other wall. These walls terminate distant from the slit in elongated wavy edges between which a front wall of the burner unit extends, with this front wall being also of a wavy configuration and being formed with discharge openings through which gas discharges. These openings are respectively situated adjacent the ridges of the walls so as to form two rows of openings with the openings of one row laterally offset from and longitudinally staggered with respect to the openings of the other row.

United States Patent [72] Inventor Tredicesimo Luciano Ferroli San Bonifacio, Italy [21 1 Appl. No. 767,337

[22'] Filed Oct. 14, 1968 [45] Patented Feb. 16, 1971 [73] Assignee Fer Fabbrica Europea Riscaldameuto S. p.A.

San Bonifacio, Italy [32] Priority Oct. 17, 1967 [33] Italy [3 l 99798/67 [54] GAS BURNER UNIT 3,412,940 11/1968 Ferroli Primary Examiner-Lloyd L. King Anorney-Steinberg and Blake ABSTRACT: A gas burner unit for providing a discharge of a combustible gas to mix with the surrounding air so as to support a flame. The gas burner unit has gas-receiving and gasdischarging chambers which are defined, in part, between a pair of opposed longitudinally extending sidewalls which define between themselves a narrow longitudinally extending slit through which the gas-receiving and gas-discharging chambers communicate with each other. At the gas-discharging chamber these walls are of an undulatory, wavy configuration and are in phase so that the alternating ridges and depressions of one wall are respectively in alignment with the alternating depressions and ridges of the other wall. These walls terminate distant from the slit in elongated wavy edges between which a front wall of the burner unit extends, with this front wall being also of a wavy configuration and being formed with discharge openings through which gas discharges. These openings are respectively situated adjacent the ridges of the walls so as to form two rows of openings with the openings of one row laterally offset from and longitudinally staggered with respect to the openings of the other row.

GAS BURNER UNIT This invention relates to a burner unit for fuel gases, such as liquid gas, mixed methane-gas, intended to be used along with other identical units for making up a burner for boilers, stoves, hot-air generators and like apparatus.

It is the main object of the present invention to provide a compact economical burner unit having such features as to enable:

a. a good mixing of the gas with air and, accordingly, a good combustion;

b. a substantial flame stability and density, hence enabling the use thereof in compact combustion chambers of apparatus (such as boilers and the like) having a high heat capacity, but small size.

The burner unit according to the invention is characterized by comprising at least one gas admission port, a chamber communicating with this port, at least one slit in said chamber, at least a second chamber connected with the first chamber through said slit and having a cross section at least partially increasing in a direction opposite to said slit, and at least two rows of openings in this chamber at a position substantially opposite to said slit, where the openings of one of said rows are offset to those of the other row.

According to an aspect of the invention, the rows of openings are parallel to each other and are provided on a wall of the second chamber which is located at a position opposite to the connecting slit with the first chamber.

According to a further particular aspect of the invention, two opposite walls defining the second chamber are for at least length formed of a series of subsequent projecting depressions enlarging in a direction opposite to the slit, the outlet openings lying between a depression of one of sad walls and the opposite ridge of the other wall, as displaced to the related ridge.

The invention will be better understood from the following detailed description, given by mere way of example and thus of not limitation, of a particular embodiment thereof, as shown in the accompanying drawings, in which:

FIG. 1 is a perspective view showing the burner unit;

FIG. 2 is a schematic top view showing a portion of the bumer unit;

FIG. 3 is an enlarged sectional view substantially corresponding to line IIIIII of FIG. I;

FIG. 4 is a sectional view according to Line IV-IV of FIG. 3;

FIG. 5 is a sectional view according to line V-V of FIG. 3; and

FIG. 6 is a fragmentary sectional view substantially corresponding to line Vl-VI of FIG. 3.

The burner unit, as shown in the drawings, is made of stamped, bent and welded plate so as to provide an inner cavity or chamber 2 communicating with a gas supply header conduit (not shown) through an opening 7 thereof. Chamber 2 has a cross section decreasing from opening 7, i.e. from the side edges of the latter to the two opposite ends of the unit.

The lower wall of chamber 2, designated at 1 and in which said opening 7 is positioned, is located at a position opposite to a narrow slit 3 connecting said first chamber 2 with a second chamber, designated as a whole at 4.

On the opposite sides, said chamber 4 is defined by walls, designated as a whole at 5 and 5'.

Walls 5 and 5 are characterized by a series of alternate ridges 6 and depressions 8. More particularly, these ridges can initiate at some distance from slit 3 (as shown in FIG. 3, where this slit is at the level of line K of FIG. I), or from the slit itself. These ridges, of an arcuated cross section, increase from the base thereof (that is, from the location nearest said slit 3) gradually to the front wall, designated as a whole at 10, closing said chamber 4 at the top. instead, intermediate depressions 8 gradually decrease as moving away from slit 3.

In a plan view (FIG. 2), the burner unit is defined on two sides by two undulations substantially in phase with each other, signifying a correspondence between a ridge 6 of wall 5 and a depression 8 of the other wall 5', and vice versa.

Two rows of holes 12 and R3 are provided on top of wall It). Such holes or openings are of a circular shape and the two rows are parallel to each other. Holes 13 in one of the rows are offset to holes 12 in the other row, so that hole 12 is more displaced to ridge 6 of wall 5 than to depression 3, which is located at an opposite position and pertains to wall 5. The opposite is for holes 13 which are positioned closer to ridge 6 of wall 5' than the opposite depression 8 pertaining to wall 5. As clearly shown in FIG. 3, a series of conduits is thus provided, the conduits laterally communicating with one another, each of which opening to one of said openings 12 or 13, but with a different inclination due to the different inclination of ridges 6 of walls 5 and 5'.

Front surface 10 is substantially arcuated (as seen in crosssectional view) and openings 12 and 13 have the longitudinal axes thereof, designated by Cin FIG. 3, inclined to an ideal median plane Z-Z (FIG. 3) of the burner unit. Substantially, axes C of holes 12 define a plane, and axes C of holes 13 define a plane as well. Such planes are inclined on the opposite sides of a plane (22) forming the plane of symmetry for chamber 2.

Fuel gas enters chamber 2 through opening 7 and thereafter moves through slit 3 to second chamber 4, dispensing thereat through each nozzle which can be idealized as formed of a ridge 6 in one of the walls of chamber 4, the opposite depression of the other wall, and hole 12 or 13 which is not located on the line of plane Z-Z of the burner unit, but closer to the ridge and inclined to said plane Z-Z. Thus it will be seen that with this structure of the invention the gas burner unit includes a gas-receiving chamber 2 and a gas-discharging chamber 4. These chambers are defined, in part, between the pair of opposed walls which are shown in section in FIG. 3, and these walls closely approach each other to define the longitudinal, narrow slit 3 through which the chambers 2 and 4 communicate with each other. At the chamber 4 the opposed walls have the undulatory, wavy configuration apparent from FIGS. 2 and 3, as well as FIGS. 4 and 5. These wavy walls are in phase so that the ridges and alternating depressions of one wall are respectively in alignment with the depressions and alternating ridges of the other wall. As a result the top or front wall 10 has the wavy configuration apparent from FIG. 2, and of course the series of openings 12 and 13 are situated at the successive ridges adjacent thereto in order to provide the pair of rows of openings 12 and 13 which have their openings arranged in the staggered manner apparent from FIG. 2. The chamber 4 gradually tapers so that it is of the gradually increasing cross section from the slit 3 to the wall 10, and the arrangement in this connection is such that the ridges 6 become of gradually greater arcuate length longitudinally of the walls while the depressions 8 become longitudinally of gradually smaller length longitudinally of the walls, in a direction from the slit 3 toward the wall 10. This is particularly apparent from a comparison of FIGS. 4 and 5. As a result of this construction although the burner unit may have a relatively short length from one depression to the next along one of the walls at the chamber a, nevertheless because of the bulging ridge between the pair of successive depressions there is a considerable length of curved wall extending around each opening to provide an exceedingly effective burning of the combustible gas with the openings arranged in a fairly dense manner.

By this construction, there is provided a good gas-air mixing, a good combustion and a substantially continuous fiame throughout the burner with a substantial flame density along the longitudinal length for the burner unit owing to the particular arrangement for the openings on two parallel rows, but with offset openings.

Iclaim:

1. A gas burner unit having gas-receiving and gas-discharging chambers defined, in part, between a pair of longitudinally extending sidewalls which define between themselves a longitudinal narrow slit through which the chambers communicate with each other, said walls having at said gas-discharging chamber a wavy, undulating configuration with the alternating ridges and depressions of one wall respectively aligned with the alternating depressions and ridges of the other wall so that said walls are in phase, and said walls respectively terminating distant from said slit in a pair of wavy edges, and a front wall extending between and connected to said edges and having a wavy configuration conforming thereto, said front wall being formed with two rows of staggered openings respectively situated adjacent the ridges, and the longitudinally extending sidewalls being located at said gas-discharging chamber nearest to each other at said slit and at a gradually increasing distance from each other toward said wavy edges interconnected by said front wall, so that said gas-discharging 

1. A gas burner unit having gas-receiving and gas-discharging chambers defined, in part, between a pair of longitudinally extending sidewalls which define between themselves a longitudinal narrow slit through which the chambers communicate with each other, said walls having at said gas-discharging chamber a wavy, undulating configuration with the alternating ridges and depressions of one wall respectively aligned with the alternating depressions and ridges of the other wall so that said walls are ''''in phase,'''' and said walls respectively terminating distant from said slit in a pair of wavy edges, and a front wall extending between and connected to said edges and having a wavy configuration conforming thereto, said front wall being formed with two rows of staggered openings respectively situated adjacent the ridges, and the longitudinally extending sidewalls being located at said gas-discharging chamber nearest to each other at said slit and at a gradually increasing distance from each other toward said wavy edges interconnected by said front wall, so that said gas-discharging chamber is tapered and gradually increases in cross section from said slit toward said front wall.
 2. The combination of claim 1 and wherein said front wall is of a curved cross section and has an inner concave surface directed toward said slit.
 3. The combination of claim 1 and wherein said sidewalls are straight at the region of said slit and have in a direction away from said slit toward said wavy edges ridges of gradually increasing arcuate length and depressions of gradually diminishing length longitudinally of the unit. 